archiving on Unix?

[Charles Hedrick]

Does anyone know of an archiving system similar to TOPS-20's?  We'd
like users to be able to say "archive <filenames>" and have them
moved to tapes automatically.  Then we'd like them to be able to say
"retrieve <filenames>" and have them come back.  Presumably it
would be easy enough to write a program that would append a request
to a file and then have a shell script read the file and create
a script that invoked tar or something.  (Indeed we already have
a "retrieve" command that does just this, to issue retrieve requests
against our old TOPS-20 archive tapes.)  But I'd like to avoid
reinventing known technology.